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Chronic Fatigue Syndrome (CFS)

What is chronic fatigue syndrome?

Chronic fatigue syndrome (CFS) is characterized by profound tiredness, regardless of bed rest. Its symptoms may worsen with physical or mental activity. CFS can happen suddenly and last for years. The condition affects more females than males.

What causes chronic fatigue syndrome?

The cause of CFS is not known.

Who is at risk for chronic fatigue syndrome?

Because the cause of CFS is not known, it’s hard to know what might put someone at risk for getting the condition. However, certain factors are seen more often in people with CFS. These factors include:

Gender. CFS happens up to 2 to 4 times more often in women than in men.

Age. CFS commonly affects middle-aged people, but people of any age can get it.

What are the symptoms of chronic fatigue syndrome?

Symptoms of CFS often mimic the flu. These are the most common symptoms. But symptoms may occur a bit different in each person.

Sensitivity to light

Headache

Tender lymph nodes

Fatigue and weakness

Muscle and joint pain

Inability to concentrate

Insomnia

Forgetfulness

Mood swings

Confusion

Low-grade fever

Depression

The symptoms of CFS may look like other medical conditions. Always talk with your healthcare provider for a diagnosis.

How is chronic fatigue syndrome diagnosed?

CFS diagnosis requires ruling out other possible conditions. According to the Institute of Medicine, a CFS diagnosis requires all 3 of the following symptoms:

Having to cut back greatly on activities you did before the illness. Severe and chronic tiredness must have lasted for more than 6 months, and other health conditions have been ruled out. Rest does not ease these symptoms.

Severe tiredness after physical activity. The fatigue gets worsen after physical or mental stress that you could handle before the illness started.

Sleep that doesn't refresh you.

In addition, one of the following symptoms must be present:

Difficulty thinking that gets worsen under pressure.

Orthostatic intolerance. This means standing upright makes symptoms worse. Lying back down or elevating your feet may ease the symptoms but does not fully get rid of them.

Living with chronic fatigue syndrome

There is currently no cure for CFS. Dealing with the severe fatigue can be very challenging. It's important to work with your healthcare provider to find treatments that help you. Some people find counseling or support groups helpful.

When should I call my healthcare provider?

Call your healthcare provider if your symptoms get worse or you have new symptoms.